Prof. North investigates how plants cope with stressful environments such as hot deserts, dry shrub lands, tropical tree canopies, and fire-prone landscapes, with a primary focus on how plants cope with limited water.
Research Description
Prof. North鈥檚 work ranges in scale from remote sensing of chlorophyll fluorescence and carbon dioxide uptake at the tree canopy level, to the expression of aquaporins and proton pumps at the level of cell membranes, to interactions between the soil microbiome and plant roots. Much of her research centers on the ways in which plant traits such as the dimensions and distribution of vascular tissue influence plant responses to stressful conditions. Recently, North and her students have investigated how the joint stresses of decreasing water supplies and increasing heat influence the ability of plants to photosynthesize. On top of such stresses, plants may be increasingly exposed to fire, and their ability to recover from fire has been a focus of the lab since the Los Angeles fires in the winter of 2025. North鈥檚 fieldwork has taken her and her students throughout southern California and to the rain forest in Costa Rica.
Students in the North lab can work in both the field and in the field. Field equipment includes:
- Devices to measure and record temperature and water content of soils, plants, and air.路
- Devices to measure chlorophyll fluorescence and plant gas exchange.
- Light meters to track photosynthetically active radiation.
In the laboratory, in addition to sensitive equipment to measure plant physiology, both light and scanning electron microscopy are used to image plant cellular and subcellular responses to varying types of stress.
Student Research Opportunities
In addition to joining North in any plant investigations resembling those described above, students are welcome to join in the process of updating and digitizing dried plant specimens in the Occidental Herbarium and thereby learn about plant identification, conservation, and curation.
Courses
Plant Form & Function (Bio 250)
Flora of Southern California (Bio 275)
Plant Physiological Ecology (Bio 380).
Prof. North also teaches in the California Environment Semester and co-directs the COSMOS program.
Selected Publications
*Asterisks indicate SA国际传媒 student coauthors.
North, G. B., E. K. Brinton, *T. L. Kho, *K. Fukui, *F. D. R. Maharaj, *A. Fung, *M. Ranganath, *J. H. Shiina. 2023. Acid Waters in tank bromeliads: Causes and potential consequences. American Journal of Botany
North, G. B., Brinton, E. K., *Browne, M. G., *Gillman, M. G., Roddy, A. B.,*Kho, T. L., *Wang, E., *Fung, V. F., Brodersen, C. R. 2019. Hydraulic conductance, resistance, and resilience: how leaves of a tropical epiphyte respond to drought. American Journal of Botany 106: 1鈥15.
*Bogue, R. R., Schwandner, F. M., Fisher, J. B., Pavlick, R., Magney, T. S., Famiglietti, C. A., Cawse-Nicholson, K., Yadav, V., Linick, J. P., North, G. B., and *Duarte, E. 2019. Plant responses to volcanically elevated CO2 in two Costa Rican forests Biogeosciences 16: 1343鈥1360
Magney, T. S., Frankenberg, C., K缨hler, P., North, G. B., Davis, T. S., Dold, C., Dutta, D., Fisher, J. B., Grossmann, K., *Harrington, A., Hatfield, J., Stutz, J., Sun, Y., Porcar-Castell, A. 2019. Disentangling changes in the spectral shape of chlorophyll fluorescence: Implications for remote sensing of photosynthesis. Journal of Geophysical Research: Biogeosciences.
Lynch, F. H., North, G. B., Page, B. S., and *Faulwell, C.J . 2018. Analysis of a hybrid numerical method 鈥 decomposing leaf hydraulic conductance. Letters in Biomathematics 5: 98-112.
North, G. B., *Browne, M. G., *Fukui, K. ,*Maharaj, F. D.R.,*Phillips, C. A., and *Woodside, W. T. 2016. A tale of two plasticities: leaf hydraulic conductances and related traits diverge for two tropical epiphytes from contrasting light environments. Plant, Cell & Environment, doi:
Coleman-Derr, D., Desgarennes, D., Fonseca-Garcia, C., Gross, S., Clingenpeel, S., Woyke, T., North, G., Visel, A , Partida-Martinez, L. P. & Tringe, S. G. 2015. Plant compartment and biogeography affect microbiome composition in cultivated and native Agave species. New Phytologist, 209: 798-811
North, G. B., F. H. Lynch, F. D. R. Maharaj*, C. A. Phillips*, and W. T. Woodside*. 2013. Leaf hydraulic conductance for a tank bromeliad: axial and radial pathways for moving and conserving water. Frontiers in Plant Science 4(78).
Garrett, T. Y.*, C-V. Huynh* and G. B. North. 2010. Root contraction helps protect the 鈥渓iving rock鈥 cactus Ariocarpus fissuratus from lethal high temperatures when growing in rocky soil. American Journal of Botany 97(12): 1鈥11.
Pratt, R. B., G. B. North, A. L. Jacobsen, F. W. Ewers and S.D. Davis. 2009. Xylem root and shoot hydraulics is linked to life history type in chaparral seedlings (Rhamnaceae). Functional Ecology doi: 10.1111/j.1365-2435.2009.01613.x